Shift control method and system for an automatic transmission

Abstract

Disclosed is a shift control method for an automatic transmission, including the steps of; detecting a present vehicle speed, determining whether a present shift stage is lower than a predetermined shift stage, and measuring a change of throttle opening degree when an accelerator pedal is released; determining whether the change is realized in less than a predetermined amount of time when the present shift stage is determined to be lower than the predetermined shift stage, thereby determining whether the throttle opening is abruptly changed; and performing a skip upshift operation by more than two stages when the throttle opening is determined to be abruptly changed. Further, disclosed is a shift control system for realizing the above method.

What is claimed is: 
     
       1. A shift control method for an automatic transmission, comprising the steps of: detecting a present vehicle speed, determining whether a present shift stage is lower than a predetermined shift stage, and measuring a change of throttle opening degree when an accelerator pedal is released;   determining whether the change is realized in less than a predetermined amount of time when the present shift stage is determined to be lower than the predetermined shift stage, thereby determining whether the throttle opening is abruptly changed; and   performing a skip upshift operation by more than two stages when the throttle opening is determined to be abruptly changed.   
     
     
       2. A shift control method for an automatic transmission, comprising the steps of: (a) detecting a present vehicle speed and a present shift stage, and reading a signal regarding an accelerator pedal;   (b) determining if the accelerator pedal is released;   (c) determining if the present shift stage is first or second shift stage;   (d) detecting if a throttle opening is changed when the condition of step (c) is satisfied;   (e) measuring an amount of time during which the throttle opening degree is changed;   (f) determining that the amount of time is below a predetermined amount of time; and   (g) performing a skip upshift by two shift stages when the condition of step (f) is satisfied.   
     
     
       3. The shift control method according to claim 2, wherein a general upshift logic is carried out when the condition of step (c) is not satisfied. 
     
     
       4. The shift control method according to claim 2, wherein a general upshift logic is carried out when the condition of step (f) is not satisfied. 
     
     
       5. A shift control system for an automatic transmission, comprising: vehicle condition detecting means for detecting a present vehicle condition such as shift stage, throttle opening degree and vehicle speed;   a timer for measuring an amount of time during which the throttle opening degree is changed, when the vehicle condition detecting means detects a change of the throttle opening degree;   control means for controlling overall shift operations such as upshift and downshift processes according to signals from said vehicle condition detecting means and said timer; and   driving means for driving each operative part in the automatic transmission according to control signals from said control means.   
     
     
       6. The shift control system of claim 5, wherein said vehicle condition detecting means comprises: shift range detecting means for outputting a signal corresponding to a shift range;   throttle opening degree detecting means for detecting the opening degree of the throttle indexed by the accelerator pedal and outputting a signal corresponding to the detected opening degree; and   vehicle speed detecting means for detecting a vehicle speed and outputting a signal corresponding to the detected vehicle speed.   
     
     
       7. A shift control method for an automatic transmission, comprising the steps of: (a) determining whether a present shift stage is lower than a predetermined shift stage;   (b) detecting over time at least one vehicle operating condition correlated to throttle opening;   (c) determining whether the throttle opening is abruptly changed based on the detected vehicle operating condition; and   (d) performing a skip upshift operation by more than two stages when the throttle opening is determined to be abruptly changed and the present shift stage is determined to be lower than a predetermined shift stage.   
     
     
       8. The method of claim 7, wherein the predetermined shift stage is the highest or second-highest shift stage. 
     
     
       9. The method of claim 7, wherein the vehicle operating condition is position of an accelerator pedal. 
     
     
       10. The method of claim 7, wherein the vehicle operating condition is vehicle speed. 
     
     
       11. The method of claim 7, wherein the determining whether the throttle opening is abruptly changed step comprises: monitoring a change rate in the vehicle operating condition over time;   comparing the monitored change rate and a predetermined change rate in the vehicle operating condition over time; and   determining an abrupt change in the throttle opening if the monitored change rate exceeds the predetermined change rate.   
     
     
       12. An automatic transmission, comprising: at least one sensor detecting at least one vehicle operating condition correlated to throttle opening;   a controller determining whether the throttle opening is abruptly changed based on the detected vehicle operating condition and controlling the automatic transmission to perform a skip upshift operation by more than two stages when the throttle opening is determined to be abruptly changed.   
     
     
       13. The automatic transmission of claim 12 wherein the vehicle operating condition is position of an accelerator pedal. 
     
     
       14. The automatic transmission of claim 12 wherein the vehicle operating condition is vehicle speed. 
     
     
       15. The automatic transmission of claim 12 wherein the controller determines whether the throttle opening is abruptly changed by monitoring a change rate in the vehicle operating condition over time, comparing the monitored change rate and a predetermined change rate in the vehicle operating condition over time and determining an abrupt change in the throttle opening if the monitored change rate exceeds the predetermined change rate.